Correct me if I'm wrong, but price floors are when you require a product to be sold above the price that the market is dragging it towards, where an otherwise exceedingly low price would be raised. In this case it's probably making sure that American-grown agricultural commodities are not undercut by the same commodities imported from elsewhere.
Price ceilings would be something implemented to guard against price-gouging.
The one price floor that would inflict misery on the American kulaks is a price floor on labor, i.e. minimum wage (and nationwide labor protections and benefits). We know he's not about to do anything like that.